Dual connectivity power amplifier system

ABSTRACT

Aspects of this disclosure relate to a dual connectivity power amplifier system. The power amplifier system includes first and second power amplifiers that are concurrently active in a dual connectively mode. The first power amplifier is active in a different mode. A switch electrically connects the first power amplifier to different radio frequency signal paths in the dual connectivity mode and the different mode. Related methods, power amplifier modules, and wireless communication devices are disclosed.

CROSS REFERENCE TO PRIORITY APPLICATION

This application claims the benefit of priority of U.S. ProvisionalApplication No. 63/045,586, filed Jun. 29, 2020 and entitled “DUALCONNECTIVITY POWER AMPLIFIER SYSTEM,” the disclosure of which is herebyincorporated by reference in its entirety.

BACKGROUND Technical Field

Embodiments of this disclosure relate to power amplifier systemsarranged to transmit radio frequency signals.

Description of Related Technology

Radio frequency (RF) communication systems can be used for transmittingand/or receiving signals of a wide range of frequencies. For example, anRF communication system can be used to wirelessly communicate RF signalsin a frequency range of about 30 kilohertz (kHz) to 300 gigahertz (GHz),such as in the range of about 410 megahertz (MHz) to about 7.125 GHz forFifth Generation (5G) cellular communications in Frequency Range 1(FR1).

Examples of RF communication systems include, but are not limited to,mobile phones, tablets, base stations, network access points,customer-premises equipment (CPE), laptops, and wearable electronics.

In certain applications, RF communications systems can transmit aplurality of RF signals simultaneously. Radio frequency power amplifierscan be used in amplifying such RF signals for transmission.

SUMMARY OF CERTAIN INVENTIVE ASPECTS

The innovations described in the claims each have several aspects, nosingle one of which is solely responsible for its desirable attributes.Without limiting the scope of the claims, some prominent features ofthis disclosure will now be briefly described.

One aspect of this disclosure is a power amplifier system arranged fordual connectivity. The power amplifier system includes a first poweramplifier, a second power amplifier, radio frequency processingcircuitry, and a switch. The first power amplifier includes an outputconfigured to provide a radio frequency signal. The first poweramplifier configured to be active in a dual connectivity mode and to beactive in a different mode. The second power amplifier is configured tobe active in the dual connectivity mode such that the first poweramplifier and the second power amplifier are concurrently active in thedual connectivity mode. The radio frequency front end processingcircuitry includes a first radio frequency signal path and a secondradio frequency signal path. The switch is configured to electricallyconnect the output of the first power amplifier to the first radiofrequency signal path in the dual connectivity mode and to electricallyconnect the output of the first power amplifier to the second radiofrequency signal path in the different mode.

The different mode can be a cellular communication mode. The radiofrequency signal can have a lower power in the dual connectivity modethan in the different mode. The different mode can be a secondgeneration mode. The second power amplifier can be inactive in thedifferent mode.

The dual connectivity mode can be a non-standalone fifth generationmode. The radio frequency signal can be a Long Term Evolution signal inthe dual connectivity mode, and the second power amplifier can provide aNew Radio signal in the dual connectivity mode. The radio frequencysignal can be a New Radio signal in the dual connectivity mode, and thesecond power amplifier can provide a Long Term Evolution signal in thedual connectivity mode.

The first signal path can be operatively coupled between the switch anda first antenna, and the second signal path can be operatively coupledbetween the switch and a second antenna. The first antenna can beconfigured to transmit the first radio frequency signal in the dualconnectivity mode, and the second antenna is configured to transmit thesecond radio frequency signal in the dual connectivity mode.

The power amplifier system can further include an input switchconfigured to electrically connect a first transmitter to an input ofthe first power amplifier in the dual connectivity mode, and toelectrically connect a second transmitter to the input of the firstpower amplifier in the different mode.

The power amplifier system can further include a load line coupled tothe output of the power amplifier, in which the load line can provide afirst impedance in the dual connectivity mode and provide a secondimpedance in the different mode.

The first power amplifier can have a larger bandwidth in the dualconnectivity mode than in the different mode.

Another aspect of this disclosure is a method of transmitting radiofrequency signals. The method includes generating a first radiofrequency signal in a dual connectivity mode using a first poweramplifier; generating a second radio frequency signal in the dualconnectivity mode using a second power amplifier; wirelesslytransmitting the first radio frequency signal and the second radiofrequency signal in the dual connectivity mode; changing a mode ofoperation from the dual connectivity mode to a different mode, the firstpower amplifier mode being active in the different mode; andelectrically connecting an output of the first power amplifier to adifferent radio frequency signal path for the different mode than forthe dual connectivity mode.

The first and second radio frequency signals can be uplink signals. Thewirelessly transmitting can include transmitting the first radiofrequency signal from a first antenna and wirelessly transmitting thesecond radio frequency signal from a second antenna in the dualconnectivity mode. The method can include deactivating the second poweramplifier for the different mode.

Another aspect of this disclosure is a wireless communication devicearranged for dual connectivity. The wireless communication deviceincludes a first power amplifier, a second power amplifier, and aplurality of antennas. The first power amplifier includes an outputconfigured to provide a first radio frequency signal. The first poweramplifier is configured to be active in a dual connectivity mode and tobe active in a different mode. The second power amplifier configured tobe active in the dual connectivity mode such that the first poweramplifier and the second power amplifier are concurrently active in thedual connectivity mode. The plurality of antennas includes a firstantenna and a second antenna. The first antenna is configured totransmit the first radio frequency signal in the dual connectivity mode.The second antenna is configured to transmit the second radio frequencysignal in the dual connectivity mode.

The wireless communication can include radio frequency front endprocessing circuitry including a first radio frequency signal path and asecond radio frequency signal path, and a switch configured toelectrically connect the output of the first power amplifier to thefirst radio frequency signal path in the dual connectivity mode and toelectrically connect the output of the first power amplifier to thesecond radio frequency signal path in the different mode.

The first radio frequency signal can be a Long Term Evolution signal inthe dual connectivity mode, and the second radio frequency signal can bea New Radio signal in the dual connectivity mode. The first radiofrequency signal can be a New Radio signal in the dual connectivitymode, and the second radio frequency signal can be a Long Term Evolutionsignal in the dual connectivity mode.

The different mode can be associated with a different radio accesstechnology than radio access technologies associated with the dualconnectivity mode.

The second power amplifier can be inactive in the different mode. Thedifferent mode can be a second generation mode.

The second antenna can be in communication with an output of the firstpower amplifier in the different mode. Alternatively, a third antenna ofthe plurality of antennas can be in communication with an output of thefirst power amplifier in the different mode.

The wireless communication device can be a mobile phone.

Another aspect of this disclosure is a power amplifier system thatincludes a first power amplifier, a second power amplifier, and aswitch. The first power amplifier is configured to be active in a firstmode and to be active in a second mode. The first power amplifierincludes an output configured to provide a radio frequency signalassociated with a different radio access technology in the first modethan in the second mode. The second power amplifier is configured to beactive in the first mode such that the first power amplifier and thesecond power amplifier are concurrently active in the first mode. Theswitch is configured to electrically connect the output of the firstpower amplifier to a first radio frequency signal path in the first modeand to electrically connect the output of the first power amplifier to asecond radio frequency signal path in the second mode.

The first mode can be a dual connectivity mode. The first mode can be acarrier aggregation mode. The first mode can be a multiple-inputmultiple-output mode.

The radio frequency signal can be associated with a fourth generationtechnology in the first mode and a second generation technology in thesecond mode. The radio frequency signal can be associated with a fifthgeneration technology in the first mode and a second generationtechnology in the second mode.

The second power amplifier can be inactive in the second mode. Thesecond mode can be a second generation mode.

The power amplifier system can include radio frequency front endprocessing circuitry that includes the first radio frequency signal pathand the second radio frequency signal path.

Another aspect of this disclosure is a wireless communication devicearranged for multiple modes. The wireless communication device includesa first power amplifier, a second power amplifier, and a plurality ofantennas. The first power amplifier is configured to be active in afirst mode and to be active in a second mode. The first power amplifierincludes an output configured to provide a first radio frequency signalassociated with a different radio access technology in the first modethan in the second mode. The second power amplifier is configured to beactive in the second mode. The plurality of antennas includes a firstantenna and a second antenna. The first antenna is configured totransmit the first radio frequency signal from the first power amplifierin the first mode. The second antenna is configured to transmit a secondradio frequency signal from the second power amplifier in the firstmode.

The wireless communication device can include radio frequency front endprocessing circuitry including a first radio frequency signal path and asecond radio frequency signal path, and a switch configured toelectrically connect the output of the first power amplifier to thefirst radio frequency signal path in the first mode and to electricallyconnect the output of the first power amplifier to the second radiofrequency signal path in the second mode.

The first mode can be a dual connectivity mode. The first mode can be amultiple input multiple-output mode.

The first radio frequency signal can be associated with a first cellularradio access technology in the first mode, and the second radiofrequency signal can be associated with a second radio access technologyin the first mode, where the second radio access technology beingdifferent than the first radio access technology. The first radiofrequency signal can be a Long Term Evolution signal in the first mode,and the first radio frequency signal can be a second generationtechnology signal in the second mode. The first radio frequency signalcan be a New Radio signal in the first mode, and the first radiofrequency signal can be a second generation technology signal in thesecond mode.

The first antenna can be in communication with an output of the firstpower amplifier in the second mode. The second antenna can be incommunication with an output of the first power amplifier in the secondmode. A third antenna of the plurality of antennas can be incommunication with an output of the first power amplifier in the secondmode.

Another aspect of this disclosure is a method of generating radiofrequency signals. The method includes generating radio frequencysignals in a first mode using a first power amplifier and a second poweramplifier that are concurrently active; and activating the first poweramplifier for radio signal amplification in a second mode, the poweramplifier providing radio frequency signal amplification associated witha different radio access technology in the second mode than the firstmode.

The first mode can be a dual connectivity mode, and the second mode canbe a second generation (2G) mode.

The method can include electrically connecting an output of the firstpower amplifier to a first signal path for the first mode, andelectrically connecting the output of the first power amplifier to asecond signal path for the second mode.

The method can include deactivating the second power amplifier for thedifferent mode.

For purposes of summarizing the disclosure, certain aspects, advantagesand novel features of the innovations have been described herein. It isto be understood that not necessarily all such advantages may beachieved in accordance with any particular embodiment. Thus, theinnovations may be embodied or carried out in a manner that achieves oroptimizes one advantage or group of advantages as taught herein withoutnecessarily achieving other advantages as may be taught or suggestedherein.

The present disclosure relates to U.S. patent application Ser. No.______ [Attorney Docket SKYWRKS.1120A2], titled “MULTI-MODE POWERAMPLIFIER SYSTEM AND RELATED WIRELESS DEVICES AND METHODS,” filed oneven date herewith, the entire disclosure of which is herebyincorporated by reference herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of this disclosure will now be described, by way ofnon-limiting example, with reference to the accompanying drawings.

FIG. 1 is a diagram of an example dual connectivity network topology.

FIG. 2 is a schematic diagram of one example of a communication network.

FIG. 3 is a schematic block diagram of a power amplifier system arrangedfor dual connectivity according to an embodiment.

FIG. 4 is a schematic block diagram of part of a power amplifier moduleaccording to an embodiment.

FIG. 5 is a schematic block diagram of part of a power amplifier moduleaccording to an embodiment.

FIG. 6 is a schematic block diagram of a power amplifier system arrangedfor dual connectivity according to an embodiment.

FIG. 7 is a schematic block diagram of a power amplifier system arrangedfor dual connectivity according to an embodiment.

FIG. 8 is a schematic block diagram of a power amplifier systemaccording to an embodiment.

FIG. 9 is a schematic block diagram of a power amplifier systemaccording to an embodiment.

FIG. 10 is a schematic block diagram of a power amplifier systemaccording to an embodiment.

FIG. 11 is a schematic block diagram of a power amplifier system with aninput switch according to an embodiment.

FIG. 12 is a schematic block diagram of a power amplifier system with anadjustable load line according to an embodiment.

FIG. 13A is a schematic diagram of one example of a communication linkusing carrier aggregation.

FIG. 13B illustrates various examples of uplink carrier aggregation forthe communication link of FIG. 13A.

FIG. 14A is a schematic diagram of one example of an uplink channelusing multi-input and multi-output (MIMO) communications.

FIG. 14B is schematic diagram of another example of an uplink channelusing MIMO communications.

FIG. 15 is a schematic diagram of one embodiment of a mobile device.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

The following description of certain embodiments presents variousdescriptions of specific embodiments. However, the innovations describedherein can be embodied in a multitude of different ways, for example, asdefined and covered by the claims. In this description, reference ismade to the drawings where like reference numerals can indicateidentical or functionally similar elements. It will be understood thatelements illustrated in the figures are not necessarily drawn to scale.Moreover, it will be understood that certain embodiments can includemore elements than illustrated in a drawing and/or a subset of theelements illustrated in a drawing. Further, some embodiments canincorporate any suitable combination of features from two or moredrawings. The headings provided herein are for convenience only and arenot intended to affect the meaning or scope of the claims.

The International Telecommunication Union (ITU) is a specialized agencyof the United Nations (UN) responsible for global issues concerninginformation and communication technologies, including the shared globaluse of radio spectrum.

The 3rd Generation Partnership Project (3GPP) is a collaboration betweengroups of telecommunications standard bodies across the world, such asthe Association of Radio Industries and Businesses (ARIB), theTelecommunications Technology Committee (TTC), the China CommunicationsStandards Association (CCSA), the Alliance for TelecommunicationsIndustry Solutions (ATIS), the Telecommunications Technology Association(TTA), the European Telecommunications Standards Institute (ETSI), andthe Telecommunications Standards Development Society, India (TSDSI).

Working within the scope of the ITU, 3GPP develops and maintainstechnical specifications for a variety of mobile communicationtechnologies, including, for example, second generation (2G) technology(for instance, Global System for Mobile Communications (GSM) andEnhanced Data Rates for GSM Evolution (EDGE)), third generation (3G)technology (for instance, Universal Mobile Telecommunications System(UMTS) and High Speed Packet Access (HSPA)), and fourth generation (4G)technology (for instance, Long Term Evolution (LTE) and LTE-Advanced).

The technical specifications controlled by 3GPP can be expanded andrevised by specification releases, which can span multiple years andspecify a breadth of new features and evolutions.

In one example, 3GPP introduced carrier aggregation (CA) for LTE inRelease 10. Although initially introduced with two downlink carriers,3GPP expanded carrier aggregation in Release 14 to include up to fivedownlink carriers and up to three uplink carriers. Other examples of newfeatures and evolutions provided by 3GPP releases include, but are notlimited to, License Assisted Access (LAA), enhanced LAA (eLAA),Narrowband Internet of things (NB-IOT), Vehicle-to-Everything (V2X), andHigh Power User Equipment (HPUE).

3GPP introduced Phase 1 of fifth generation (5G) technology in Release15, and is currently in the process of developing Phase 2 of 5Gtechnology in Release 16. Subsequent 3GPP releases will further evolveand expand 5G technology. 5G technology is also referred to herein as 5GNew Radio (NR).

5G NR supports or plans to support a variety of features, such ascommunications over millimeter wave spectrum, beamforming capability,high spectral efficiency waveforms, low latency communications, multipleradio numerology, and/or non-orthogonal multiple access (NOMA). Althoughsuch RF functionalities offer flexibility to networks and enhance userdata rates, supporting such features can pose a number of technicalchallenges.

The teachings herein are applicable to a wide variety of communicationsystems, including, but not limited to, communication systems usingadvanced cellular technologies, such as LTE-Advanced, LTE-Advanced Pro,and/or 5G NR.

Dual Connectivity

With the introduction of the 5G NR air interface standards, 3GPP hasallowed for the simultaneous operation of 5G and 4G standards in orderto facilitate the transition. This mode can be referred to asNon-Stand-Alone (NSA) 5G operation or E-UTRAN New Radio-DualConnectivity (EN-DC) and involves both 4G and 5G carriers beingsimultaneously transmitted from a user equipment (UE).

In certain EN-DC applications, dual connectivity NSA involves overlaying5G systems onto an existing 4G core network. For dual connectivity insuch applications, the control and synchronization between the basestation and the UE can be performed by the 4G network while the 5Gnetwork is a complementary radio access network tethered to the 4Ganchor. The 4G anchor can connect to the existing 4G network with theoverlay of 5G data/control.

FIG. 1 is a diagram of an example dual connectivity network topology.This architecture can leverage LTE legacy coverage to ensure continuityof service delivery and the progressive rollout of 5G cells. A UE 10 cansimultaneously transmit dual uplink LTE and NR carrier. The UE 10 cantransmit an uplink LTE carrier Tx1 to the eNB 11 while transmitting anuplink NR carrier Tx2 to the gNB 12 to implement dual connectivity. Anysuitable combination of uplink carriers Tx1, Tx2 and/or downlinkcarriers Rx1, Rx2 can be concurrently transmitted via wireless links inthe example network topology of FIG. 1. The eNB 11 can provide aconnection with a core network, such as an Evolved Packet Core (EPC) 14.The gNB 12 can communicate with the core network via the eNB 11. Controlplane data can be wireless communicated between the UE 10 and eNB 11.The eNB 11 can also communicate control plane data with the gNB 12.Control plane data can propagate along the paths of the dashed lines inFIG. 1. The solid lines in FIG. 1 are for data plane paths.

In the example dual connectivity topology of FIG. 1, any suitablecombinations of standardized bands and radio access technologies (e.g.,FDD, TDD, SUL, SDL) can be wirelessly transmitted and received. This canpresent technical challenges related to having multiple separate radiosand bands functioning in the UE 10. With a TDD LTE anchor point, networkoperation may be synchronous, in which case the operating modes can beconstrained to Tx1/Tx2 and Rx1/Rx2, or asynchronous which can involveTx1/Tx2, Tx1/Rx2, Rx1/Tx2, Rx1/Rx2. When the LTE anchor is a frequencydivision duplex (FDD) carrier, the TDD/FDD inter-band operation caninvolve simultaneous Tx1/Rx1/Tx2 and Tx1/Rx1/Rx2.

As discussed above, EN-DC can involve both 4G and 5G carriers beingsimultaneously transmitted from a UE. Transmitting both 4G and 5Gcarriers from a UE, such as a phone, typically involves two poweramplifiers (PAs) being active at the same time. Traditionally, havingtwo power amplifiers active simultaneously would involve the placementof one or more additional power amplifiers specifically suited for EN-DCoperation. Additional board space and expense is incurred when designingto support such EN-DC/NSA operation.

This disclosure provides systems and methods of supporting EN-DC/NSAoperation without adding additional PAs, without consuming more PrintedCircuit Board (PCB) space or physical area, and without addingsignificant expense to the supporting EN-DC/NSA operation.

Early solutions employ additional standalone power amplifiers to supportthe 4G bands during NSA/EN-DC operation. These additional poweramplifiers consume additional PCB space and come with added system cost.As an example, an LTE Band 20 (B20) and NR Band 28 (n28) NSA EN-DC caseis typically supported with an additional external low band (LB) EN-DCpower amplifier in addition to the LB Power Amplifier Module includingDuplexer (PAMiD) module. This solution involves additional PCB space andexpense to support the EN-DC case with the extra power amplifier.Another example is the LTE Band 3 (B3) and NR Band 1 (n1) NSA EN-DC casebeing supported with an additional external Mid Band (MB) EN-DC poweramplifier in a Mid Band/High Band (MB/HB) PAMiD module. This solutionalso involves additional PCB space and expense to support the EN-DC casewith the extra power amplifier.

Aspects of this disclosure relate to using an existing power amplifierto implement dual connectivity. The existing power amplifier can beactive in a dual connectivity mode and also in a different mode. Forexample, one or more existing 2G PAs can be used for both 2G and 4G/5GEN-DC applications. 2G PAs are typically included in systemimplementations as either a stand-alone module of LB and MB poweramplifiers or PAs that are integrated into one or more 4G/5G modules.Since the 2G PAs cover existing frequency bands which can overlap with asignificant portion of the desired EN-DC frequency bands and the 2G PAscurrently have load lines adequate to support the power levels specifiedfor 4G/5G EN-DC operation, these PAs can be used for dual applications.These dual applications can be supported by adding post PA switching toroute the amplifier signals to either the 2G or 4G/5G EN-DC signalpaths.

In certain instances, input switching to select either a 2G signal or a4G/5G EN-DC signal from a transmitter can be implemented. Broad-bandingof the existing 2G PAs may be desired to allow coverage of a widerfrequency range of dual connectivity band combinations. In someinstances, a load line switch for the 2G PAs can be included in order toachieve higher efficiency for dual connectivity applications at lowerpower levels given that the 2G PAs typically operate directly from thebattery and may not be able to improve the PA efficiency by dropping thePA collector voltage. Integrated couplers can be included to supportpower measurements during dual connectivity operation.

Examples of dual connectivity modes include (1) concurrent LTE Band 20and NR Band n1 transmissions and (2) concurrent Band 3 and Band n1transmissions. Concurrent transmissions of any suitable combination ofan LTE band transmission and an NR band transmission can be implemented.Any other suitable combination of concurrent transmissions associatedwith two different radio access technologies can be implemented inaccordance with any suitable principles and advantages disclosed herein.

By using the LB and MB 2G Power Amplifiers for dual connectivityoperation, the placement and cost of two additional PAs can beeliminated in a power amplifier system. By saving the additional expenseand board space for one or more additional power amplifiers, EN-DCsolutions disclosed herein provide advantages to traditional solutions.

Embodiments disclosed herein can eliminate the need to place one or moreadditional PAs to support a 4G EN-DC Band. 5G NSA operation can besupported using an existing 2G PA during a time when the 2G PA wouldpreviously have been idle. This can extend the use of the 2G PA andfacilitate the transition to 5G at a lower cost.

Although certain embodiments disclosed herein are related to dualconnectivity operation, any suitable principles and advantages disclosedherein can be implemented in other applications where a plurality ofradio frequency signals are being concurrently generated fortransmission. For instance, any suitable combination of featuresdescribed with reference to dual connectivity can be implemented inassociation with carrier aggregation. The carrier aggregation can be anuplink carrier aggregation. As another example, any suitable combinationof features described with reference to dual connectivity can beimplemented in association with multiple-input multiple-output (MIMO)communications. The MIMO communication can be an uplink MIMOcommunication. In these examples, an existing 2G PA can be used togenerate an individual carrier of a carrier aggregation or for a signalfor an individual data stream of a MIMO communication.

Communication Network

FIG. 2 is a schematic diagram of one example of a communication network20. The communication network 20 includes a macro cell base station 1, amobile device 2, a small cell base station 3, and a stationary wirelessdevice 4.

The illustrated communication network 20 of FIG. 2 supportscommunications using a variety of technologies, including, for example,4G LTE, 5G NR, and wireless local area network (WLAN), such as Wi-Fi. Inthe communication network 20, dual connectivity can be implemented withconcurrent 4G LTE and 5G NR communication with the mobile device 2.Although various examples of supported communication technologies areshown, the communication network 20 can be adapted to support a widevariety of communication technologies.

Various communication links of the communication network 20 have beendepicted in FIG. 2. The communication links can be duplexed in a widevariety of ways, including, for example, using frequency-divisionduplexing (FDD) and/or time-division duplexing (TDD). FDD is a type ofradio frequency communications that uses different frequencies fortransmitting and receiving signals. FDD can provide a number ofadvantages, such as high data rates and low latency. In contrast, TDD isa type of radio frequency communications that uses about the samefrequency for transmitting and receiving signals, and in which transmitand receive communications are switched in time. TDD can provide anumber of advantages, such as efficient use of spectrum and variableallocation of throughput between transmit and receive directions.

As shown in FIG. 2, the mobile device 2 communicates with the macro cellbase station 1 over a communication link that uses a combination of 4GLTE and 5G NR technologies. The mobile device 2 also communications withthe small cell base station 3. In the illustrated example, the mobiledevice 2 and small cell base station 3 communicate over a communicationlink that uses 5G NR, 4G LTE, and Wi-Fi technologies. In certainimplementations, enhanced license assisted access (eLAA) is used toaggregate one or more licensed frequency carriers (for instance,licensed 4G LTE and/or 5G NR frequencies), with one or more unlicensedcarriers (for instance, unlicensed Wi-Fi frequencies).

In certain implementations, the mobile device 2 communicates with themacro cell base station 2 and the small cell base station 3 using 5G NRtechnology over one or more frequency bands that are less than 7.5Gigahertz (GHz) and/or over one or more frequency bands that are greaterthan 7.5 GHz. For example, wireless communications can utilize FrequencyRange 1 (FR1), Frequency Range 2 (FR2), or a combination thereof. In oneembodiment, the mobile device 2 supports a HPUE power classspecification.

The illustrated small cell base station 3 also communicates with astationary wireless device 4. The small cell base station 3 can be used,for example, to provide broadband service using 5G NR technology. Incertain implementations, the small cell base station 3 communicates withthe stationary wireless device 4 over one or more millimeter wavefrequency bands in the frequency range of 30 GHz to 300 GHz and/or uppercentimeter wave frequency bands in the frequency range of 24 GHz to 30GHz.

In certain implementations, the small cell base station 3 communicateswith the stationary wireless device 4 using beamforming. For example,beamforming can be used to focus signal strength to overcome pathlosses, such as high loss associated with communicating over millimeterwave frequencies.

The communication network 20 of FIG. 2 includes the macro cell basestation 1 and the small cell base station 3. In certain implementations,the small cell base station 3 can operate with relatively lower power,shorter range, and/or with fewer concurrent users relative to the macrocell base station 1. The small cell base station 3 can also be referredto as a femtocell, a picocell, or a microcell.

Although the communication network 20 is illustrated as including twobase stations, the communication network 20 can be implemented toinclude more or fewer base stations and/or base stations of other types.As shown in FIG. 2, base stations can communicate with one another usingwireless communications to provide a wireless backhaul. Additionally oralternatively, base stations can communicate with one another usingwired and/or optical links.

The communication network 20 of FIG. 2 is illustrated as including onemobile device and one stationary wireless device. The mobile device 2and the stationary wireless device 4 illustrate two examples of userdevices or user equipment (UE). Although the communication network 20 isillustrated as including two user devices, the communication network 20can be used to communicate with more or fewer user devices and/or userdevices of other types. For example, user devices can include mobilephones, tablets, laptops, Internet of Things (IoT) devices, wearableelectronics, and/or a wide variety of other communications devices.

User devices of the communication network 20 can share available networkresources (for instance, available frequency spectrum) in a wide varietyof ways.

In one example, frequency division multiple access (FDMA) is used todivide a frequency band into multiple frequency carriers. Additionally,one or more carriers are allocated to a particular user. Examples ofFDMA include, but are not limited to, single carrier FDMA (SC-FDMA) andorthogonal FDMA (OFDMA). OFDMA is a multicarrier technology thatsubdivides the available bandwidth into multiple mutually orthogonalnarrowband subcarriers, which can be separately assigned to differentusers.

Other examples of shared access include, but are not limited to, timedivision multiple access (TDMA) in which a user is allocated particulartime slots for using a frequency resource, code division multiple access(CDMA) in which a frequency resource is shared amongst different usersby assigning each user device a unique code, space-divisional multipleaccess (SDMA) in which beamforming is used to provide shared access byspatial division, and non-orthogonal multiple access (NOMA) in which thepower domain is used for multiple access. For example, NOMA can be usedto serve multiple user devices at the same frequency, time, and/or code,but with different power levels.

Enhanced mobile broadband (eMBB) refers to technology for growing systemcapacity of LTE networks. For example, eMBB can refer to communicationswith a peak data rate of at least 10 Gbps and a minimum of 100 Mbps foreach user device. Ultra-reliable low latency communications (uRLLC)refers to technology for communication with very low latency, forinstance, less than 2 milliseconds. uRLLC can be used formission-critical communications such as for autonomous driving and/orremote surgery applications. Massive machine-type communications (mMTC)refers to low cost and low data rate communications associated withwireless connections to everyday objects, such as those associated withIoT applications.

The communication network 20 of FIG. 2 can be used to support a widevariety of advanced communication features, including, but not limitedto eMBB, uRLLC, and/or mMTC.

A peak data rate of a communication link (for instance, between a basestation and a user device) depends on a variety of factors. For example,peak data rate can be affected by channel bandwidth, modulation order, anumber of component carriers, and/or a number of antennas used forcommunications.

For instance, in certain implementations, a data rate of a communicationlink can be about equal to M*B*log₂(1+S/N), where M is the number ofcommunication channels, B is the channel bandwidth, and S/N is thesignal-to-noise ratio (SNR).

Accordingly, data rate of a communication link can be increased byincreasing the number of communication channels (for instance,transmitting and receiving using multiple antennas), using widerbandwidth (for instance, by aggregating carriers), and/or improving SNR(for instance, by increasing transmit power and/or improving receiversensitivity).

5G NR communication systems can employ a wide variety of techniques forenhancing data rate and/or communication performance.

Power Amplifier Systems and Modules

Dual connectivity and other modes of operation where two different poweramplifiers are concurrently active can be implemented in a variety ofpower amplifier systems. Example power amplifier systems and poweramplifier modules will be discussed with reference to FIGS. 3 to 12. Anysuitable combination of features of these example systems and/or modulescan be implemented together with each other.

Power amplifier systems can be used to generate signals of a wide rangeof frequencies. For example, certain power amplifier systems can operateusing one or more low bands (for example, RF signal bands having afrequency content of 1 GHz or less, also referred to herein as LB), oneor more mid bands (for example, RF signal bands having a frequencycontent between 1 GHz and 2.3 GHz, also referred to herein as MB), andone or more high bands (for example, RF signal bands having a frequencycontent between 2.3 GHz and 3 GHz such as a frequency content between2.3 GHz and 2.7 GHz, also referred to herein as HB.

Second generation (2G) power amplifiers (PAs) exist in a number of poweramplifier system implementations. A 2G power amplifier is arranged toamplify a 2G radio frequency (RF) signal. One or more 2G PAs can beimplemented as a stand-alone module of one or more Low Band (LB) and/orone or more Mid Band (MB) PAs. Alternatively or additionally, one ormore 2G PAs can be integrated into one or more 4G and/or 5G modules.

Since the 2G PAs can cover existing frequency bands which overlap asignificant portion of the desired EN-DC frequency bands and 2G PAs caninclude load-lines adequate to support the power levels specified for4G/5G EN-DC operation, such 2G PAs can be used in EN-DC applications.Accordingly, embodiments of this disclosure relate to using existing 2GPAs for both 2G applications and 4G/5G EN-DC applications.

Power amplifier systems can be arranged to support both 2G and EN-DCoperations for one or more PAs. Post PA switching can route a PA outputsignal to a 2G signal path in a 2G mode and to a 4G/5G EN-DC signal pathin an EN-DC mode. In some instances, input switching can selectivelyprovide a 2G signal or a 4G/5G EN-DC signal from a transmitter to a PA.Broad-banding of the existing 2G PAs may be desired to allow forcoverage of a wider frequency range of dual connectivity bandcombinations. Such broad-banding can involve increasing the bandwidth ofa PA. In certain instances, a load line switch can be included for oneor more 2G PAs in order to achieve higher efficiency for EN-DCapplications at lower power levels. This can be significant given that2G PAs can operate directly from a battery voltage without being able toincrease PA efficiency by dropping the PA collector voltage. Anysuitable combination of these features to support dual mode operation ofa PA can be implemented in association with any suitable principles andadvantages disclosed herein.

Using a power amplifier for two different modes of operation instead ofusing two separate power amplifiers can implement a power amplifiersystem with one less power amplifier. For example, by using the LB andMB 2G Power Amplifiers for EN-DC operation, two additional PAs can beeliminated from some previous EN-DC systems that implemented separatePAs for 2G mode and EN-DC mode.

FIG. 3 is a schematic block diagram of a power amplifier system 300arranged for dual connectivity according to an embodiment. In the poweramplifier system 300, 2G PAs are used for 4G/5G EN-DC applications. Bycontrast, 2G PAs have typically been inactive in an EN-DC mode incertain existing 4G/5G EN-DC applications.

As illustrated, the power amplifier system 300 includes a MB/HB module310, a LB module 320, and a diversity receive (DRX) module 330. Thepower amplifier system 300 also includes multiplexers electricallyconnected to circuitry of these modules. The multiplexers includeduplexers 332 and 334 and triplexer 336 arranged to filter radiofrequency signals. One or more of the illustrated multiplexers can beimplemented external to the illustrated modules. One or more of theillustrated multiplexers can be included as part of a module, such asone or more of the MB/HB module 310, the LB module 320, and the DRXmodule 330.

The illustrated LB module 320 includes a first 2G PA 322, a second 2G PA324, a LB PA 326, RF front end processing circuitry 327, and RFFE (RadioFrequency Front End) control circuitry 328. The first 2G PA 322 and thesecond 2G PA 324 can each be arranged for amplifying a 2G signal and foramplifying an RF signal in a dual connectivity mode. The LB PA 326 canbe arranged to amplify a LB 5G signal.

The first 2G PA 322 can be arranged to be active in a dual connectivitymode. The first 2G PA 322 can provide a 4G LTE LB signal during the dualconnectivity mode while a 5G PA of the power amplifier system 300 isalso active. Alternatively or additionally, the first 2G PA 322 canprovide a 5G signal during the dual connectivity mode while a 4G PA ofthe power amplifier system 300 is also active in instances where thefirst 2G PA 322 is capable of supporting the bandwidth for the 5Gsignal. The first 2G PA 322 can amplify a LB 2G signal in a 2G mode. Anoutput of the first 2G PA 322 can be electrically connected to differentsignal paths in the dual connectivity mode and the 2G mode.

The second 2G PA 324 can be arranged to be active in a dual connectivitymode. The second 2G PA 324 can provide a 4G LTE HB signal during thedual connectivity mode while a 5G PA of the power amplifier system 300is also active. Alternatively or additionally, the second 2G PA 324 canprovide a 5G signal during the dual connectivity mode while a 4G PA ofthe power amplifier system 300 is also active in instances where thesecond 2G PA 324 is capable of supporting the bandwidth for the 5Gsignal. The second 2G PA 324 can provide a 4G LTE MB signal during thedual connectivity mode while a 5G PA of the power amplifier system 300is also active. The second 2G PA 324 can amplify a HB 2G signal in a 2Gmode. An output of the second 2G PA 324 can be electrically connected todifferent signal paths in the dual connectivity mode and the 2G mode.

The RF front end processing circuitry 327 can include RF signal pathsarranged to process RF signals. Such signal paths can include one ormore switches, one or more filters and/or duplexers, one or morematching networks, one or more radio frequency couplers, the like, orany suitable combination thereof. The 2G PAs 322 and 324 can beelectrically connected to different respective signal paths in differentmodes so that 2G signal and signals for dual connectivity can beprocessed differently. A signal path between the first 2G PA 322 and anantenna can include circuitry of the RF processing circuitry 327 andother processing circuitry external to the LB module 320. A signal pathbetween the second 2G PA 324 and an antenna can include circuitry of theRF processing circuitry 327 and other processing circuitry external tothe LB module 320.

The illustrated MB/HB module 310 includes a MB PA 312 and associatedcapacitor 313, a HB PA 314 and associated capacitor 315, RF front endprocessing circuitry 317, and a MIPI control circuit 318 arranged toprovide control functionality. The MB PA 312 can amplify MB signals. TheMB PA 312 can be arranged to amplify 5G NR signals. The HB PA 314 canamplify HB signals. The HB PA 314 can be arranged to amplify 5G NRsignals. The RF front end processing circuitry 317 can include RF signalpaths arranged to process RF signals. Such signal paths can include oneor more switches, one or more filters and/or duplexers, one or morematching networks, one or more radio frequency couplers, the like, orany suitable combination thereof.

The diversity receive module 330 can perform signal processing onsignals received by the diversity antenna 362. The diversity receivemodule 330 can include one or more low noise amplifiers, one or morefilters and/or duplexers, one or more matching networks, one or moreswitches, one or more RF couplers, one or more power detectors, thelike, or any suitable combination thereof.

The MB/HB module 310, the LB module 320, and the DRX module 330 are incommunication with various antennas by way of various filters. Forexample, the MB/HB module 310 is in communication with a high bandantenna 342 via filter 340. The MB/HB module 310 is in communicationwith a main antenna 352 via a first filter of the triplexer 350. The LBmodule is in communication with the main antenna via a second filter ofthe triplexer 350. The DRX module 330 is in communication with adiversity receive antenna 362 via filters of the triplexer 360.

FIG. 4 is a schematic block diagram of part of a power amplifier module400 according to an embodiment. As illustrated, the power amplifiermodule 400 includes a first 2G PA 322, a second 2G PA 324, a firstfilter 422, a second filter 432, a first switch 424, and a second switch434. The part of the power amplifier module 400 can be included in theLB module 320 of FIG. 3, for example. The first filter 422, the secondfilter 432, the first switch 424, and the second switch 434 can beincluded in the RF front end processing circuitry 327 of FIG. 3 incertain applications.

The switches 424 and 434 support signal routing for 2G operation andEN-DC operation. The switches 424 and 434 function as band select/modeselect switches coupled to outputs of respective 2G PAs 322 and 324,respectively.

An output signal provided by the first 2G PA 322 can be filtered by thefirst filter 422 and provided to the first switch 424. The first filter422 can be a low pass filter. The first switch 424 can electricallyconnect the output of the first 2G PA 322 to a 2G LB signal path in a 2Gmode. The first switch 424 can electrically connect the output of thefirst 2G PA 322 to a LB EN-DC signal path in an EN-DC mode. Accordingly,the first switch 424 can route an output of the first 2G PA 322 foreither 2G or 4G/5G EN-DC operation. The 2G PA 322 can provide a radiofrequency output signal associated with a different radio accesstechnology in the EN-DC mode than in the 2G mode.

An output signal provided by the second 2G PA 324 can be filtered by thesecond filter 432 and provided to the second switch 434. The secondswitch 434 can electrically connect the output of the second 2G PA 324to a 2G signal path in a 2G mode. The second switch 434 can electricallyconnect the output of the second 2G PA 324 to a HB EN-DC signal path inan EN-DC mode. Accordingly, the second switch 434 can route an output ofthe second 2G PA 324 for either 2G or 4G/5G EN-DC operation. The 2G PA324 can provide a radio frequency output signal associated with adifferent radio access technology in the EN-DC mode than in the 2G mode.

In some embodiments (not illustrated), a supply voltage for the first 2GPA 322 and/or second 2G PA 324 can be adjusted to be different for 2Gmode and EN-DC mode.

A load line coupled to the output of the first 2G PA 322 and/or a loadline coupled to an output second 2G PA 324 can be adjusted to providedifferent impedances for 2G mode and EN-DC mode. This can reduce powerfor EN-DC mode relative to 2G mode. Adjusting impedance of a load linecan improve efficiency for the 2G mode and/or the EN-DC mode.

FIG. 5 is a schematic block diagram of part of a power amplifier module500 according to an embodiment. The power amplifier module 500 is astandalone 2G EN-DC power amplifier module. Like in the power amplifiermodule 400, the first switch 424 and the second switch 434 can routeoutputs of respective 2G PAs 322 and 324 for 2G operation and for 4G/5GEN-DC operation in the power amplifier module 500.

The power amplifier module 500 also includes radio frequency couplers522 and 532. The radio frequency couplers 522 and 532 can provide RFsamples of EN-DC signals output from the power amplifier module 500. TheRF samples can be provided to an output of the power amplifier module500 via a switch 540. Integrated radio frequency couplers 522 and 532can advantageously provide an indication of output power for EN-DCsignals provided by the power amplifier module 500 at an output of thepower amplifier module 500. This can support power measurements duringEN-DC operation. The power amplifier module 500 also includes a RFFEcontrol circuit 550 that provides control functionality.

FIG. 6 is a schematic block diagram of a power amplifier system 600arranged for dual connectivity according to an embodiment. A 2G PA isused for a 4G/5G EN-DC application in the power amplifier system 600. Asillustrated, the power amplifier system 600 includes a LB module 620 anda DRX module 630. The power amplifier system 600 also includesmultiplexers electrically connected to circuitry of these modules. Themultiplexers include a duplexer 634 and a triplexer 636. One or more ofthe illustrated multiplexers can be implemented external to theillustrated modules. One or more of the illustrated multiplexers can beincluded as part of a module, such as the LB module 620 and/or the DRXmodule 630. One or more of the illustrated multiplexers can include afilter that is included as part of a module and another filter that isexternal to the module.

As an example, the power amplifier system 600 can support a LB EN-DCmode for 4G LTE Band 20 and 5G NR Band n28. In this example, the first2G PA 322 can provide a 4G Band 20 signal while the LB PA 326 provides a5G Band n28 signal. The duplexer 634 can be a Band n28 duplexer and thetriplexer can include a Band 20 transmit filter. The first 2G PA 322 canprovide an amplified RF signal to the Band 20 transmit filter of thetriplexer 636 via the first switch 424 in the EN-DC mode. The LB PA 326can concurrently provide another amplified RF signal to a transmitfilter of duplexer 624 via a switch 622 and circuitry of the RFfrequency processing circuitry 627.

FIG. 7 is a schematic block diagram of a power amplifier system 700arranged for dual connectivity according to an embodiment. A 2G PA isused for a 4G/5G EN-DC application in the power amplifier system 700. Asillustrated, the power amplifier system 700 includes a MB/HB module 710and a LB module 620. The power amplifier system 700 also includesmultiplexers electrically connected to circuitry of these modules. Themultiplexers include a duplexer 634 and a duplexer 732. One or more ofthe illustrated multiplexers can be implemented external to theillustrated modules. One or more of the illustrated multiplexers can beincluded as part of a module, such as the LB module 620 and/or the MB/HBmodule 710. One or more of the illustrated multiplexers can include afilter that is included as part of a module and another filter that isexternal to the module.

As an example, the power amplifier system 700 can support a MB EN-DCmode for 4G LTE Band 3 and 5G NR Band n1. In this example, the second 2GPA 324 can provide a 4G Band 3 signal while the MB PA 312 provides a 5GBand n1 signal. The duplexer 732 can be a Band 3 duplexer. The second 2GPA 324 can provide an amplified RF signal to the Band 3 transmit filterof the duplexer 732 via the second switch 434 in the EN-DC mode. The MBPA 312 can concurrently provide another amplified RF signal to a Band n1transmit filter of the RF frequency processing circuitry 717.

In an embodiment, a power amplifier system can include the LB module 620of FIGS. 6 and 7, the DRX module 630 of FIG. 6, and the HB/MB module 710of FIG. 7. Such an embodiment can implement the dual connectivityfeatures described with reference to FIGS. 6 and 7.

Example EN-DC cases are discussed with reference to FIGS. 6 and 7. Anysuitable dual connectivity case can be implemented in accordance withany suitable principles and advantages disclosed herein. In someinstances, one or more 2G PAs can be arranged to have broader bandwidthto support any suitable dual connectivity cases.

FIG. 8 is a schematic block diagram of a power amplifier system 800according to an embodiment. As illustrated, the power amplifier system800 includes a first PA 802, a second PA 804, a first switch 810, afirst signal path 822, a second signal path 824, a third signal path826, a second switch 830, a first antenna 842, and a second antenna 844.

The first power amplifier 802 is arranged to be active in a first modeand to be active in a second mode. The second power amplifier 804 isarranged to be active in the first mode such that the first poweramplifier 802 and the second power amplifier 804 are concurrently activein the first mode. The second power amplifier 804 can be inactive in thesecond mode.

The first mode can be a dual connectivity mode, a carrier aggregationmode, a MIMO mode, or another mode where both the first power amplifier802 and the second power amplifier 804 are active. As an example, thefirst mode can be a dual connectivity mode. The second mode can be a 2Gmode, for example.

In the first mode, the first power amplifier 802 and the second poweramplifier 804 can generate radio frequency signals in a common bandrange (e.g., LB, MB, or HB) or within different band ranges (e.g., firstpower amplifier 802 in different one of LB, MB, or HB than second poweramplifier 804). The first power amplifier 802 and the second poweramplifier 804 can generate radio frequency signals in any band rangecombination of Table 1 in the first mode.

TABLE 1 First PA LB MB HB HB MB HB LB MB LB Second PA LB MB HB MB HB LBHB LB MB

The first power amplifier 802 has an output configured to provide aradio frequency signal associated with a different radio accesstechnology in the first mode than in the second mode. For example, thefirst power amplifier 802 can provide a 4G signal in the first mode anda 2G signal in the second mode. As another example, the first poweramplifier 802 can provide a 5G signal in the first mode and a 2G signalin the second mode. Accordingly, the first power amplifier 802 canprovide radio frequency signals associated with different radio accesstechnologies in different modes.

In certain instances, the first power amplifier 802 is arranged to havea broader bandwidth to operate in the first mode and the second modethan a similar power amplifier arranged to operate in only one of thesemodes.

The first switch 810 is arranged to electrically connect the output ofthe first power amplifier 802 to the first radio frequency signal path822 in the first mode and to electrically connect the output of thefirst power amplifier 802 to the second radio frequency signal path 824in the second mode. The first and second radio frequency signal paths822 and 824 can process an output signal provided by the first poweramplifier 802 differently to meet the specifications for the first modeand the second mode, respectively.

The first radio frequency signal path 822 can be arranged to process anoutput signal provided by the first power amplifier 802 in the firstmode. The first radio frequency signal path 822 can include one or morefilters (e.g., one or more filters having a passband associated with thefirst mode), one or more matching networks, one or more switches, one ormore radio frequency couplers, the like, or any suitable combinationthereof. The first radio frequency signal path 822 can include radiofrequency processing circuitry of a power amplifier module of any ofFIGS. 3-7 and/or circuitry external to a mode amplifier module.

The second radio frequency signal path 824 can be arranged to process anoutput signal provided by the first power amplifier 802 in the secondmode. The second radio frequency signal path 824 can include one or morefilters (e.g., one or more filters having a passband associated with thesecond mode), one or more matching networks, one or more switches, oneor more radio frequency couplers, the like, or any suitable combinationthereof. The second radio frequency signal path 824 can include radiofrequency processing circuitry of a power amplifier module of any ofFIGS. 3-7 and/or circuitry external to a mode amplifier module.

In some applications, a power supply voltage for the first poweramplifier 802 can be adjusted for toggling between the first mode andthe second mode. The first power amplifier 802 can operate with a lowerpower in the first mode than in the second mode. The first poweramplifier 802 can output a radio frequency signal associated with adifferent radio access technology in the second mode than in the firstmode. The different radio access technologies can both be cellular radioaccess technologies.

In certain applications, the second power amplifier 804 can provide anoutput signal associated with a different radio access technology thanthe first power amplifier 802 in the first mode. For example, in thefirst mode, the second power amplifier 804 can provide a 5G signal andthe first power amplifier 802 can provide a 4G signal. As anotherexample, in the first mode, the second power amplifier 804 can provide a4G signal and the first power amplifier 802 can provide a 5G signal. Thedifferent radio access technologies can both be cellular radio accesstechnologies.

In some other applications, the first power amplifier 802 and the secondpower amplifier 804 can provide output signals associated with the sameradio access technology in the first mode. For example, in the firstmode, the second power amplifier 804 and the first power amplifier 802can both provide 4G signals in the first mode. As another example, inthe first mode, the second power amplifier 804 and the first poweramplifier 802 can both provide 5G signals in the first mode. In theseexamples, the first power amplifier 802 and the second power amplifier804 can provide signals for carrier aggregation and/or MIMOcommunications in the first mode.

The third radio frequency signal path 826 can be arranged to process anoutput signal provided by the second power amplifier 804 in the firstmode. The third radio frequency signal path 826 can include one or morefilters, one or more matching networks, one or more switches, one ormore radio frequency couplers, the like, or any suitable combinationthereof.

The second switch 830 can electrically connect the third signal path 826to the second antenna 844 in the first mode and electrically connect thesecond signal path 824 to the second antenna 844 in the second mode. Inthe first mode, the output signal from the first power amplifier 802 canbe transmitted from the first antenna 842 and the output signal from thesecond power amplifier 804 can be transmitted from the second antenna844. In the second mode, the output signal from the first poweramplifier 802 can be transmitted from the second antenna 844. The secondantenna 844 can be a main antenna of a mobile device in certainapplications.

FIG. 9 is a schematic block diagram of a power amplifier system 900according to an embodiment. As illustrated, the power amplifier system900 includes a first PA 802, a second PA 804, a first switch 810, afirst signal path 822, a second signal path 824, a third signal path826, a second switch 930, a first antenna 942, and a second antenna 944.In the power amplifier system 900, signals from the first poweramplifier 802 are transmitted from a different antenna than signals fromthe second power amplifier 804. The second switch 930 is arranged toelectrically connect the first signal path 822 to the first antenna 942in the first mode and to electrically connect the second signal path 824to the second antenna 944 in the second mode. Thus, the output signalfrom the first power amplifier 802 can be transmitted from the firstantenna 942 in both the first mode and the second mode. Together theswitches 810 and 930 couple the first power amplifier 802 to the firstantenna 942 via different signal paths in different modes.

FIG. 10 is a schematic block diagram of a power amplifier system 1000according to an embodiment. As illustrated, the power amplifier systemincludes a first PA 802, a second PA 804, a first switch 810, a firstsignal path 822, a second signal path 824, a third signal path 826, afirst antenna 1042, a second antenna 1043, and a third antenna 1044. Inthe power amplifier system 1000, an output signal from the first poweramplifier 802 is transmitted from different antennas in different modesand also from a different antenna that an output signal from the secondpower amplifier 804. In the first mode, the output signal from the firstpower amplifier 802 can be transmitted from the first antenna 1042 whilethe output signal from the second power amplifier 804 is transmittedfrom the third antenna 1044. In the second mode, the output from thefirst power amplifier 802 can be transmitted from the second antenna1043.

In some other applications, the first power amplifier 802 and the secondpower amplifier 804 can both provide a respective radio frequency signalto the same antenna in a mode in which both the first power amplifier802 and the second power amplifier 804 are concurrently active. In suchapplications, the first power amplifier 802 and the second poweramplifier 804 can generate radio frequency signals with differentfrequency contents that are frequency domain multiplexed and thenprovided to the same antenna. For example, the power amplifiers 802 and804 can generate radio frequency signals with different frequencycontents for a carrier aggregation and the radio frequency signals canbe combined by a multiplexer for transmission from the same antenna.

In certain applications, input switching can select which transmitter toelectrically connect to an input of a power amplifier for differentmodes. For example, an input switch for a 2G PA can provide a 2G signalto the input of the 2G PA in a 2G mode and provide a 4G/5G EN-DC signalto the input of the 2G PA in an EN-DC mode.

FIG. 11 is a schematic block diagram of a power amplifier system 1100with an input switch 1102 according to an embodiment. The input switch1102 can electrically connect different transmitters to an input of thepower amplifier 802 in different modes. The input switch 1102 can beimplemented together with any suitable principles and advantagesdisclosed herein. For example, the input switch 1102 can be added to anyother embodiments of power amplifier systems and/or modules disclosedherein. The input switch 1102 can be included in a packaged module thatalso includes any suitable combination of features of the poweramplifier module 400 of FIG. 4. The input switch 1102 can be included ina packaged module that also includes any suitable combination offeatures of the power amplifier module 500 of FIG. 5.

In certain applications, a load line on an output of a power amplifieroperable in a plurality of modes can be adjustable for the differentmodes. For example, an adjustable load line on an output of a 2G PA canprovide improved efficiency at a desired operating power level byadjusting when toggling between 2G mode and EN-DC mode. Load lineswitching can adjust the load line and improve the operating efficiencyif the target output power levels for 2G and EN-DC are significantlydifferent.

FIG. 12 is a schematic block diagram of a power amplifier system 1200with an adjustable load line 1202 according to an embodiment. Theadjustable load line 1202 can adjust impedance of the load line foroperating in different modes. For example, the adjustable load line 1202can provide a different impedance for a 2G mode than for an EN-DC modein order to improve and/or optimize efficiency at target operating powerlevels for each mode. The adjustable load line 1202 can implement loadline switching to adjust impedance.

The adjustable load line 1202 can be implemented together with anysuitable principles and advantages disclosed herein. For example, theadjustable load line 1202 can be added to any other embodiments of poweramplifier systems and/or modules disclosed herein. The adjustable loadline 1202 can be included in a packaged module that also includes anysuitable combination of features of the power amplifier module 400 ofFIG. 4. The adjustable load line 1202 can be included in a packagedmodule that also includes any suitable combination of features of thepower amplifier module 500 of FIG. 5. The adjustable load line 1202 canbe included in a packaged module that also includes the input switch1102 of FIG. 11 and any suitable combination of features of the poweramplifier module 400 of FIG. 4. The adjustable load line 1202 can beincluded in a packaged module that also includes the input switch 1102of FIG. 11 and any suitable combination of features of the poweramplifier module 500 of FIG. 5.

Carrier Aggregation

FIG. 13A is a schematic diagram of one example of a communication linkusing carrier aggregation. Carrier aggregation can be used to widenbandwidth of the communication link by supporting communications overmultiple frequency carriers, thereby increasing user data rates andenhancing network capacity by utilizing fragmented spectrum allocations.Power amplifiers disclosed herein can be implemented in carrieraggregation applications.

In the illustrated example, the communication link is provided between abase station 1321 and a mobile device 1322. As shown in FIG. 13A, thecommunications link includes a downlink channel used for RFcommunications from the base station 1321 to the mobile device 1322, andan uplink channel used for RF communications from the mobile device 1322to the base station 1321.

Although FIG. 13A illustrates carrier aggregation in the context of FDDcommunications, carrier aggregation can also be used for TDDcommunications.

In certain implementations, a communication link can provideasymmetrical data rates for a downlink channel and an uplink channel.For example, a communication link can be used to support a relativelyhigh downlink data rate to enable high speed streaming of multimediacontent to a mobile device, while providing a relatively slower datarate for uploading data from the mobile device to the cloud.

In the illustrated example, the base station 1321 and the mobile device1322 communicate via carrier aggregation, which can be used toselectively increase bandwidth of the communication link. Carrieraggregation includes contiguous aggregation, in which contiguouscarriers within the same operating frequency band are aggregated.Carrier aggregation can also be non-contiguous, and can include carriersseparated in frequency within a common band or in different bands.

In the example shown in FIG. 13A, the uplink channel includes threeaggregated component carriers f_(UL1), f_(UL2), and f_(UL3).Additionally, the downlink channel includes five aggregated componentcarriers f_(DL1), f_(DL2), f_(DL3), f_(DL4), and f_(DL5). Although oneexample of component carrier aggregation is shown, more or fewercarriers can be aggregated for uplink and/or downlink. Moreover, anumber of aggregated carriers can be varied over time to achieve desireduplink and downlink data rates.

For example, a number of aggregated carriers for uplink and/or downlinkcommunications with respect to a particular mobile device can changeover time. For example, the number of aggregated carriers can change asthe device moves through the communication network and/or as networkusage changes over time.

FIG. 13B illustrates various examples of uplink carrier aggregation forthe communication link of FIG. 13A. FIG. 13B includes a first carrieraggregation scenario 1331, a second carrier aggregation scenario 1332,and a third carrier aggregation scenario 1333, which schematicallydepict three types of carrier aggregation.

The carrier aggregation scenarios 1331-33 illustrate different spectrumallocations for a first component carrier f_(UL1), a second componentcarrier f_(UL2), and a third component carrier f_(UL3). Although FIG.13B is illustrated in the context of aggregating three componentcarriers, carrier aggregation can be used to aggregate more or fewercarriers. Moreover, although illustrated in the context of uplink, theaggregation scenarios are also applicable to downlink.

The first carrier aggregation scenario 1331 illustrates intra-bandcontiguous carrier aggregation, in which component carriers that areadjacent in frequency and in a common frequency band are aggregated. Forexample, the first carrier aggregation scenario 1331 depicts aggregationof component carriers f_(UL1), f_(UL2), and f_(UL3) that are contiguousand located within a first frequency band BAND1.

With continuing reference to FIG. 13B, the second carrier aggregationscenario 1332 illustrates intra-band non-continuous carrier aggregation,in which two or more components carriers that are non-adjacent infrequency and within a common frequency band are aggregated. Forexample, the second carrier aggregation scenario 1332 depictsaggregation of component carriers f_(UL1), f_(UL2), and f_(UL3) that arenon-contiguous, but located within a first frequency band BAND1.

The third carrier aggregation scenario 1333 illustrates inter-bandnon-contiguous carrier aggregation, in which component carriers that arenon-adjacent in frequency and in multiple frequency bands areaggregated. For example, the third carrier aggregation scenario 1333depicts aggregation of component carriers f_(UL1) and f_(UL2) of a firstfrequency band BAND1 with component carrier f_(UL3) of a secondfrequency band BAND2.

With reference to FIGS. 13A-13B, the individual component carriers usedin carrier aggregation can be of a variety of frequencies, including,for example, frequency carriers in the same band or in multiple bands.Additionally, carrier aggregation is applicable to implementations inwhich the individual component carriers are of about the same bandwidthas well as to implementations in which the individual component carriershave different bandwidths.

Certain communication networks allocate a particular user device with aprimary component carrier (PCC) or anchor carrier for uplink and a PCCfor downlink. Additionally, when the mobile device communicates using asingle frequency carrier for uplink or downlink, the user devicecommunicates using the PCC. To enhance bandwidth for uplinkcommunications, the uplink PCC can be aggregated with one or more uplinksecondary component carriers (SCCs). Additionally, to enhance bandwidthfor downlink communications, the downlink PCC can be aggregated with oneor more downlink SCCs.

In certain implementations, a communication network provides a networkcell for each component carrier. Additionally, a primary cell canoperate using a PCC, while a secondary cell can operate using a SCC. Theprimary and secondary cells may have different coverage areas, forinstance, due to differences in frequencies of carriers and/or networkenvironment.

License assisted access (LAA) refers to downlink carrier aggregation inwhich a licensed frequency carrier associated with a mobile operator isaggregated with a frequency carrier in unlicensed spectrum, such asWi-Fi. LAA employs a downlink PCC in the licensed spectrum that carriescontrol and signaling information associated with the communicationlink, while unlicensed spectrum is aggregated for wider downlinkbandwidth when available. LAA can operate with dynamic adjustment ofsecondary carriers to avoid Wi-Fi users and/or to coexist with Wi-Fiusers. Enhanced license assisted access (eLAA) refers to an evolution ofLAA that aggregates licensed and unlicensed spectrum for both downlinkand uplink.

MIMO Communications

FIG. 14A is a schematic diagram of one example of an uplink channelusing multi-input and multi-output (MIMO) communications. Poweramplifiers disclosed herein can be implemented in MIMO communicationsapplications.

MIMO communications use multiple antennas for simultaneouslycommunicating multiple data streams over common frequency spectrum. Incertain implementations, the data streams operate with differentreference signals to enhance data reception at the receiver. MIMOcommunications benefit from higher SNR, improved coding, and/or reducedsignal interference due to spatial multiplexing differences of the radioenvironment.

MIMO order refers to a number of separate data streams sent or received.For instance, MIMO order for uplink communications can be described by anumber of transmit antennas of UE, such as a mobile device, and a numberof receive antennas of a base station. For example, 2×2 UL MIMO refersto MIMO uplink communications using two UE antennas and two base stationantennas. Additionally, 4×4 UL MIMO refers to MIMO uplink communicationsusing four UE antennas and four base station antennas.

In the example shown in FIG. 14A, uplink MIMO communications areprovided by transmitting using N antennas 1444 a, 1444 b, 1444 c, . . .1444 n of the mobile device 1442 and receiving using M antennas 1443 a,1443 b, 1443 c, . . . 1443 m of the base station 1441. Accordingly, FIG.14A illustrates an example of n×m UL MIMO.

By increasing the level or order of MIMO, bandwidth of an uplink channeland/or a downlink channel can be increased.

MIMO communications are applicable to communication links of a varietyof types, such as FDD communication links and TDD communication links.

FIG. 14B is schematic diagram of another example of an uplink channelusing MIMO communications. In the example shown in FIG. 14B, uplink MIMOcommunications are provided by transmitting using N antennas 1444 a,1444 b, 1444 c, . . . 1444 n of the mobile device 1442. Additionally, afirst portion of the uplink transmissions are received using M antennas1443 a 1, 1443 b 1, 1443 c 1, . . . 1443 m 1 of a first base station1441 a, while a second portion of the uplink transmissions are receivedusing M antennas 1443 a 2, 1443 b 2, 1443 c 2, . . . 1443 m 2 of asecond base station 1441 b. Additionally, the first base station 1441 aand the second base station 1441 b communicate with one another overwired, optical, and/or wireless links.

The MIMO scenario of FIG. 14B illustrates an example in which multiplebase stations cooperate to facilitate MIMO communications.

Mobile Devices

The power amplifier systems disclosed herein can be included in wirelesscommunication devices, such as mobile devices. A power amplifier systemin accordance with any suitable principles and advantages disclosedherein can be implemented in any suitable wireless communication device.An example of such a wireless communication device will be discussedwith reference to FIG. 15.

FIG. 15 is a schematic diagram of one embodiment of a mobile device1500. The mobile device 1500 includes a baseband system 1501, atransceiver 1502, a front end system 1503, antennas 1504, a powermanagement system 1505, a memory 1506, a user interface 1507, and abattery 1508.

The mobile device 1500 can be used communicate using a wide variety ofcommunications technologies, including, but not limited to, 2G, 3G, 4G(including LTE, LTE-Advanced, and LTE-Advanced Pro), 5G NR, WLAN (forinstance, Wi-Fi), WPAN (for instance, Bluetooth and ZigBee), WMAN (forinstance, WiMax), and/or GPS technologies.

The transceiver 1502 generates RF signals for transmission and processesincoming RF signals received from the antennas 1504. It will beunderstood that various functionalities associated with the transmissionand receiving of RF signals can be achieved by one or more componentsthat are collectively represented in FIG. 15 as the transceiver 1502. Inone example, separate components (for instance, separate circuits ordies) can be provided for handling certain types of RF signals.

The front end system 1503 aids in conditioning signals transmitted toand/or received from the antennas 1504. In the illustrated embodiment,the front end system 1503 includes antenna tuning circuitry 1510, poweramplifiers (PAs) 1511, low noise amplifiers (LNAs) 1512, filters 1513,switches 1514, and signal splitting/combining circuitry 1515. However,other implementations are possible.

For example, the front end system 1503 can provide a number offunctionalities, including, but not limited to, amplifying signals fortransmission, amplifying received signals, filtering signals, switchingbetween different bands, switching between different power modes,switching between transmission and receiving modes, duplexing ofsignals, multiplexing of signals (for instance, diplexing ortriplexing), or some combination thereof.

In certain implementations, the mobile device 1500 supports carrieraggregation, thereby providing flexibility to increase peak data rates.Carrier aggregation can be used for both Frequency Division Duplexing(FDD) and Time Division Duplexing (TDD), and may be used to aggregate aplurality of carriers or channels. Carrier aggregation includescontiguous aggregation, in which contiguous carriers within the sameoperating frequency band are aggregated. Carrier aggregation can also benon-contiguous, and can include carriers separated in frequency within acommon band or in different bands.

The antennas 1504 can include antennas used for a wide variety of typesof communications. For example, the antennas 1504 can include antennasfor transmitting and/or receiving signals associated with a wide varietyof frequencies and communications standards.

In certain implementations, the antennas 1504 support MIMOcommunications and/or switched diversity communications. For example,MIMO communications use multiple antennas for communicating multipledata streams over a single radio frequency channel. MIMO communicationsbenefit from higher signal to noise ratio, improved coding, and/orreduced signal interference due to spatial multiplexing differences ofthe radio environment. Switched diversity refers to communications inwhich a particular antenna is selected for operation at a particulartime. For example, a switch can be used to select a particular antennafrom a group of antennas based on a variety of factors, such as anobserved bit error rate and/or a signal strength indicator.

The mobile device 1500 can operate with beamforming in certainimplementations. For example, the front end system 1503 can includeamplifiers having controllable gain and phase shifters havingcontrollable phase to provide beam formation and directivity fortransmission and/or reception of signals using the antennas 1504. Forexample, in the context of signal transmission, the amplitude and phasesof the transmit signals provided to the antennas 1504 are controlledsuch that radiated signals from the antennas 1504 combine usingconstructive and destructive interference to generate an aggregatetransmit signal exhibiting beam-like qualities with more signal strengthpropagating in a given direction. In the context of signal reception,the amplitude and phases are controlled such that more signal energy isreceived when the signal is arriving to the antennas 1504 from aparticular direction. In certain implementations, the antennas 1504include one or more arrays of antenna elements to enhance beamforming.

The baseband system 1501 is coupled to the user interface 1507 tofacilitate processing of various user input and output (I/O), such asvoice and data. The baseband system 1501 provides the transceiver 1502with digital representations of transmit signals, which the transceiver1502 processes to generate RF signals for transmission. The basebandsystem 1501 also processes digital representations of received signalsprovided by the transceiver 1502. As shown in FIG. 15, the basebandsystem 1501 is coupled to the memory 1506 of facilitate operation of themobile device 1500.

The memory 1506 can be used for a wide variety of purposes, such asstoring data and/or instructions to facilitate the operation of themobile device 1500 and/or to provide storage of user information.

The power management system 1505 provides a number of power managementfunctions of the mobile device 1500. In certain implementations, thepower management system 1505 includes a PA supply control circuit thatcontrols the supply voltages of the power amplifiers 1511. For example,the power management system 1505 can be configured to change the supplyvoltage(s) provided to one or more of the power amplifiers 1511 toimprove efficiency, such as power added efficiency (PAE).

As shown in FIG. 15, the power management system 1505 receives a batteryvoltage from the battery 1508. The battery 1508 can be any suitablebattery for use in the mobile device 1500, including, for example, alithium-ion battery.

APPLICATIONS, TERMINOLOGY, AND CONCLUSION

Any of the embodiments described above can be implemented in associationwith mobile devices such as cellular handsets. The principles andadvantages of the embodiments can be used for any systems or apparatus,such as any uplink wireless communication device, that could benefitfrom any of the embodiments described herein. The teachings herein areapplicable to a variety of systems. Although this disclosure includesexample embodiments, the teachings described herein can be applied to avariety of structures. Any of the principles and advantages discussedherein can be implemented in association with RF circuits configured toamplify and process signals having a frequency in a range from about 30kHz to 300 GHz, such as in a frequency range from about 450 MHz to 8.5GHz. Power amplifier systems disclosed herein can generate RF signals atfrequencies within FR1 of a 5G NR specification.

Aspects of this disclosure can be implemented in various electronicdevices. Examples of the electronic devices can include, but are notlimited to, consumer electronic products, parts of the consumerelectronic products such as packaged radio frequency modules, uplinkwireless communication devices, wireless communication infrastructure,electronic test equipment, etc. Examples of the electronic devices caninclude, but are not limited to, a mobile phone such as a smart phone, awearable computing device such as a smart watch or an ear piece, atelephone, a television, a computer monitor, a computer, a modem, ahand-held computer, a laptop computer, a tablet computer, a microwave, arefrigerator, a vehicular electronics system such as an automotiveelectronics system, a robot such as an industrial robot, an Internet ofthings device, a stereo system, a digital music player, a radio, acamera such as a digital camera, a portable memory chip, a homeappliance such as a washer or a dryer, a peripheral device, a wristwatch, a clock, etc. Further, the electronic devices can includeunfinished products.

Unless the context indicates otherwise, throughout the description andthe claims, the words “comprise,” “comprising,” “include,” “including”and the like are to generally be construed in an inclusive sense, asopposed to an exclusive or exhaustive sense; that is to say, in thesense of “including, but not limited to.” Conditional language usedherein, such as, among others, “can,” “could,” “might,” “may,” “e.g.,”“for example,” “such as” and the like, unless specifically statedotherwise, or otherwise understood within the context as used, isgenerally intended to convey that certain embodiments include, whileother embodiments do not include, certain features, elements and/orstates. The word “coupled”, as generally used herein, refers to two ormore elements that may be either directly connected, or connected by wayof one or more intermediate elements. Likewise, the word “connected”, asgenerally used herein, refers to two or more elements that may be eitherdirectly connected, or connected by way of one or more intermediateelements. Additionally, the words “herein,” “above,” “below,” and wordsof similar import, when used in this application, shall refer to thisapplication as a whole and not to any particular portions of thisapplication. Where the context permits, words in the above DetailedDescription using the singular or plural number may also include theplural or singular number respectively.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the disclosure. Indeed, the novel power amplifier systems,radio frequency front ends, wireless communication devices, and methodsdescribed herein may be embodied in a variety of other forms.Furthermore, various omissions, substitutions and changes in the form ofthe power amplifier systems, radio frequency front ends, wirelesscommunication devices, and methods described herein may be made withoutdeparting from the spirit of the disclosure. For example, while blocksare presented in a given arrangement, alternative embodiments mayperform similar functionalities with different components and/or circuittopologies, and some blocks may be deleted, moved, added, subdivided,combined, and/or modified. Each of these blocks may be implemented in avariety of different ways. Any suitable combination of the elementsand/or acts of the various embodiments described above can be combinedto provide further embodiments. The accompanying claims and theirequivalents are intended to cover such forms or modifications as wouldfall within the scope and spirit of the disclosure.

What is claimed is:
 1. A power amplifier system arranged for dualconnectivity, the power amplifier system comprising: a first poweramplifier including an output configured to provide a radio frequencysignal, the first power amplifier configured to be active in a dualconnectivity mode and to be active in a different mode; a second poweramplifier configured to be active in the dual connectivity mode suchthat the first power amplifier and the second power amplifier areconcurrently active in the dual connectivity mode; radio frequency frontend processing circuitry including a first radio frequency signal pathand a second radio frequency signal path; and a switch configured toelectrically connect the output of the first power amplifier to thefirst radio frequency signal path in the dual connectivity mode and toelectrically connect the output of the first power amplifier to thesecond radio frequency signal path in the different mode.
 2. The poweramplifier system of claim 1 wherein the different mode is a cellularcommunication mode.
 3. The power amplifier system of claim 1 wherein theradio frequency signal has a lower power in the dual connectivity modethan in the different mode.
 4. The power amplifier system of claim 1wherein the different mode is a second generation mode.
 5. The poweramplifier system of claim 1 wherein the second power amplifier isinactive in the different mode.
 6. The power amplifier system of claim 1wherein the dual connectivity mode is a non-standalone fifth generationmode.
 7. The power amplifier system of claim 1 wherein the radiofrequency signal is a Long Term Evolution signal in the dualconnectivity mode, and the second power amplifier is configured toprovide a New Radio signal in the dual connectivity mode.
 8. The poweramplifier system of claim 1 wherein the radio frequency signal is a NewRadio signal in the dual connectivity mode, and the second poweramplifier is configured to provide a Long Term Evolution signal in thedual connectivity mode.
 9. The power amplifier system of claim 1 whereinthe first signal path is operatively coupled between the switch and afirst antenna, and the second signal path is operatively coupled betweenthe switch and a second antenna.
 10. The power amplifier system of claim9 wherein the first antenna is configured to transmit the radiofrequency signal in the dual connectivity mode, and the second antennais configured to transmit a second radio frequency signal from thesecond power amplifier in the dual connectivity mode.
 11. The poweramplifier system of claim 1 further comprising an input switchconfigured to electrically connect a first transmitter to an input ofthe first power amplifier in the dual connectivity mode, and toelectrically connect a second transmitter to the input of the firstpower amplifier in the different mode.
 12. The power amplifier system ofclaim 1 further comprising a load line coupled to the output of thefirst power amplifier, the load line being configured to provide a firstimpedance in the dual connectivity mode and to provide a secondimpedance in the different mode, the first impedance being differentthan the second impedance.
 13. The power amplifier system of claim 1wherein the first power amplifier is configured to have a largerbandwidth in the dual connectivity mode than in the different mode. 14.A method of transmitting radio frequency signals, the method comprising:generating a first radio frequency signal in a dual connectivity modeusing a first power amplifier; generating a second radio frequencysignal in the dual connectivity mode using a second power amplifier;wirelessly transmitting the first radio frequency signal and the secondradio frequency signal in the dual connectivity mode; changing a mode ofoperation from the dual connectivity mode to a different mode, the firstpower amplifier being active in the different mode; and electricallyconnecting an output of the first power amplifier to a different radiofrequency signal path for the different mode than for the dualconnectivity mode.
 15. The method of claim 14 further comprisingdeactivating the second power amplifier for the different mode.
 16. Awireless communication device arranged for dual connectivity, thewireless communication device comprising: a first power amplifierincluding an output configured to provide a first radio frequencysignal, the first power amplifier configured to be active in a dualconnectivity mode and to be active in a different mode; a second poweramplifier configured to be active in the dual connectivity mode suchthat the first power amplifier and the second power amplifier areconcurrently active in the dual connectivity mode; and a plurality ofantennas including a first antenna and a second antenna, the firstantenna configured to transmit the first radio frequency signal in thedual connectivity mode, and the second antenna configured to transmitthe second radio frequency signal in the dual connectivity mode.
 17. Thewireless communication device of claim 16 further comprising radiofrequency front end processing circuitry including a first radiofrequency signal path and a second radio frequency signal path, and aswitch configured to electrically connect the output of the first poweramplifier to the first radio frequency signal path in the dualconnectivity mode and to electrically connect the output of the firstpower amplifier to the second radio frequency signal path in thedifferent mode.
 18. The wireless communication device of claim 16wherein the first radio frequency signal is a Long Term Evolution signalin the dual connectivity mode, and the second radio frequency signal isa New Radio signal in the dual connectivity mode.
 19. The wirelesscommunication device of claim 16 wherein the first radio frequencysignal is a New Radio signal in the dual connectivity mode, and thesecond radio frequency signal is a Long Term Evolution signal in thedual connectivity mode.
 20. The wireless communication device of claim16 wherein the different mode is associated with a different radioaccess technology than radio access technologies associated with thedual connectivity mode.